<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="app">
     <input type="text" v-model="url" placeholder="输入网址">
    <a :href="url">访问</a>
</div>
<!--引入vue-->
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.6.14/vue.js"></script>
<script>
    let v = new Vue({
        el:"#app",
        data:{
          url:""
        }
    })
</script>

</body>
</html>